Omit redundant prefixes or suffixes in library naming

Makefile.system

@@ -1520,10 +1520,18 @@ ifndef LIBNAMEPREFIX
 LIBNAMEPREFIX =
 endif
 
+SYMPREFIX=$(SYMBOLPREFIX)
+ifeq ($(SYMBOLPREFIX),$(LIBNAMEPREFIX))
+SYMPREFIX=
+endif
+SYMSUFFIX=$(SYMBOLSUFFIX)
+ifeq ($(SYMBOLSUFFIX),$(LIBNAMESUFFIX))
+SYMSUFFIX=
+endif
 ifndef LIBNAMESUFFIX
-LIBNAMEBASE = $(SYMBOLPREFIX)$(LIBSONAMEBASE)$(SYMBOLSUFFIX)
+LIBNAMEBASE = $(SYMPREFIX)$(LIBSONAMEBASE)$(SYMSUFFIX)
 else
-LIBNAMEBASE = $(SYMBOLPREFIX)$(LIBSONAMEBASE)$(SYMBOLSUFFIX)$(LIBNAMESUFFIX)
+LIBNAMEBASE = $(SYMPREFIX)$(LIBSONAMEBASE)$(SYMSUFFIX)$(LIBNAMESUFFIX)
 endif
 
 ifeq ($(OSNAME), CYGWIN_NT)